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Berger K, Coker E, Rauch S, Eskenazi B, Balmes J, Kogut K, Holland N, Calafat AM, Harley K. Prenatal phthalate, paraben, and phenol exposure and childhood allergic and respiratory outcomes: Evaluating exposure to chemical mixtures. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 725:138418. [PMID: 32302842 PMCID: PMC7255953 DOI: 10.1016/j.scitotenv.2020.138418] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 03/31/2020] [Accepted: 04/01/2020] [Indexed: 05/10/2023]
Abstract
BACKGROUND Chemicals found in personal care products and plastics have been associated with asthma, allergies, and lung function, but methods to address real life exposure to mixtures of these chemicals have not been applied to these associations. METHODS We quantified urinary concentrations of eleven phthalate metabolites, four parabens, and five other phenols in mothers twice during pregnancy and assessed probable asthma, aeroallergies, and lung function in their age seven children. We implemented Bayesian Profile Regression (BPR) to cluster women by their exposures to these chemicals and tested the clusters for differences in outcome measurements. We used Bayesian Kernel Machine Regression (BKMR) to fit biomarkers into one model as joint independent variables. RESULTS BPR clustered women into seven groups characterized by patterns of personal care product and plastic use, though there were no significant differences in outcomes across clusters. BKMR showed that monocarboxyisooctyl phthalate and 2,4-dichlorophenol were associated with probable asthma (predicted probability of probable asthma per IQR of biomarker z-score (standard deviation) = 0.08 (0.09) and 0.11 (0.12), respectively) and poorer lung function (predicted probability per IQR = -0.07 (0.05) and -0.07 (0.06), respectively), and that mono(3-carboxypropyl) phthalate and bisphenol A were associated with aeroallergies (predicted probability per IQR = 0.13 (0.09) and 0.11 (0.08), respectively). Several biomarkers demonstrated positive additive effects on other associations. CONCLUSIONS BPR and BKMR are useful tools to evaluate associations of biomarker concentrations within a mixture of exposure and should supplement single-chemical regression models when data allow.
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Fadadu R, Grimes B, Balmes J, Wei M. 413 Wildfire-associated air pollution impacts clinic visits for itch and atopic dermatitis. J Invest Dermatol 2020. [DOI: 10.1016/j.jid.2020.03.421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Mortimer K, Lesosky M, Semple S, Malava J, Katundu C, Crampin A, Wang D, Weston W, Pope D, Havens D, Gordon SB, Balmes J. Pneumonia and Exposure to Household Air Pollution in Children Under the Age of 5 Years in Rural Malawi: Findings From the Cooking and Pneumonia Study. Chest 2020; 158:501-511. [PMID: 32311349 PMCID: PMC7417377 DOI: 10.1016/j.chest.2020.03.064] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 03/16/2020] [Accepted: 03/28/2020] [Indexed: 01/06/2023] Open
Abstract
Background Exposure to household air pollution is associated with an increased risk of pneumonia in children in low- and middle-income countries; however, exposure-response data are limited, and there are uncertainties around the extent to which biomass-fueled cookstoves can reduce these exposures. Research Question What is the association between exposure to household air pollution and pneumonia in children under the age of 5 years in rural Malawi and what are the effects of a biomass-fueled cookstove intervention on personal exposure to household air pollution? Study Design and Methods We measured personal exposure to carbon monoxide (CO; 48 hours of continuous measurement and transcutaneous carboxyhemoglobin) every 6 months in children who participated in a cluster-randomized controlled trial of a cleaner burning biomass-fueled cookstove intervention to prevent pneumonia in children under the age of 5 years in rural Malawi (the Cooking And Pneumonia Study). Exposure-response and multivariable analyses were done. Results We recruited 1805 (928 intervention; 877 control) children (mean age, 25.6 months; 50.6% female). We found no evidence of an association between exposure to CO (incident rate ratio, 1.0; 95% CI, 0.967 to 1.014; P = .53) or carboxyhemoglobin (incident rate ratio, 1.00; 95% CI, 0.993 to 1.003; P = .41) in children who experienced pneumonia vs those who did not. Median exposure to CO in the intervention and control groups was was 0.34 (interquartile range, 0.15 to 0.81) and 0.37 parts per million (interquartile range, 0.15 toa 0.97), respectively. The group difference in means was 0.46 (95% CI, −0.95 to 0.012; P = .06). Interpretation Exposure to CO in our population was low with no association seen between exposure to CO and pneumonia incidence and no effect of the Cooking And Pneumonia Study intervention on these exposures. These findings suggest that CO may not be an appropriate measure of household air pollution exposure in settings such as rural Malawi and that there is a need to develop ways to measure particulate matter exposures directly in young children instead. Clinical Trial Registration ISRCTN59448623.
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Fedak KM, Good N, Walker ES, Balmes J, Brook RD, Clark ML, Cole-Hunter T, Devlin R, L'Orange C, Luckasen G, Mehaffy J, Shelton R, Wilson A, Volckens J, Peel JL. Acute changes in lung function following controlled exposure to cookstove air pollution in the subclinical tests of volunteers exposed to smoke (STOVES) study. Inhal Toxicol 2020; 32:115-123. [PMID: 32297528 DOI: 10.1080/08958378.2020.1751750] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Background: Exposure to household air pollution generated as a result of cooking and heating is a leading contributor to global disease. The effects of cookstove-generated air pollution on adult lung function, however, remain uncertain.Objectives: We investigated acute responses in lung function following controlled exposures to cookstove-generated air pollution.Methods: We recruited 48 healthy adult volunteers to undergo six two-hour treatments: a filtered-air control and emissions from five different stoves with fine particulate matter (PM2.5) targets from 10 to 500 µg/m3. Spirometry was conducted prior to exposure and immediately, and three and 24 h post-exposure. Mixed-effect models were used to estimate differences in post-exposure lung function for stove treatments versus control.Results: Immediately post-exposure, lung function was lower compared to the control for the three highest PM2.5-level stoves. The largest differences were for the fan rocket stove (target 250 µg/m3; forced vital capacity (FVC): -60 mL, 95% confidence interval (95% CI) -135, 15; forced expiratory volume (FEV1): -51 mL, 95% CI -117, 16; mid-expiratory flow (FEF25-75): -116 mL/s, 95% CI -239, 8). At 3 h post-exposure, lung function was lower compared to the control for all stove treatments; effects were of similar magnitude for all stoves. At 24 h post-exposure, results were consistent with a null association for FVC and FEV1; FEF25-75 was lower relative to the control for the gasifier, fan rocket, and three stone fire.Conclusions: Patterns suggesting short-term decreases in lung function follow from exposure to cookstove air pollution even for stove exposures with low PM2.5 levels.
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Blount RJ, Pascopella L, Barry P, Zabner J, Stapleton EM, Flood J, Balmes J, Nahid P, Catanzaro DG. Residential urban tree canopy is associated with decreased mortality during tuberculosis treatment in California. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 711:134580. [PMID: 32000313 PMCID: PMC6995452 DOI: 10.1016/j.scitotenv.2019.134580] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 09/18/2019] [Accepted: 09/19/2019] [Indexed: 06/10/2023]
Abstract
Trees can sequester air pollutants, and air pollution is associated with poor tuberculosis outcomes. However, the health impacts of urban trees on tuberculosis patients are unknown. To elucidate the effects of urban tree canopy on mortality during tuberculosis treatment, we evaluated patients diagnosed with active tuberculosis in California from 2000 through 2012, obtaining patient data from the California tuberculosis registry. Our primary outcome was all-cause mortality during tuberculosis treatment. We determined percent tree cover using 1 mresolution color infrared orthoimagery categorized into land cover classes, then linked tree cover to four circular buffer zones of 50-300 m radii around patient residential addresses. We used the Kaplan-Meier method to estimate survival probabilities and Cox regression models to determine mortality hazard ratios, adjusting for demographic, socioeconomic, and clinical covariates. Our cohort included 33,962 tuberculosis patients of median age 47, 59% male, 51% unemployed, and 4.9% HIV positive. Tuberculosis was microbiologically confirmed in 79%, and 1.17% were multi-drug resistant (MDR). Median tree cover was 7.9% (50 m buffer). Patients were followed for 23,280 person-years with 2370 deaths during tuberculosis treatment resulting in a crude mortality rate of 1018 deaths per 10,000 person-years. Increasing tree cover quintiles were associated with decreasing mortality risk during tuberculosis treatment in all buffers, and the magnitude of association decreased incrementally with increasing buffer radius: In the 50 m buffer, patients living in neighborhoods with the highest quintile tree cover experienced a 22% reduction in mortality (HR 0.78, 95%CI 0.68-0.90) compared to those living in lowest quintile tree cover; whereas for 100, 200, and 300 m buffers, a 21%, 13%, and 11% mortality risk reduction was evident. In conclusion, urban tree canopy was associated with decreased mortality during tuberculosis treatment even after adjusting for multiple demographic, socioeconomic, and clinical factors, suggesting that trees might play a role in improving tuberculosis outcomes.
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Khan MA, Hira-Smith M, Ahmed SI, Yunus M, Hasan SMT, Liaw J, Balmes J, Raqib R, Yuan Y, Kalman D, Roh T, Steinmaus C, Smith AH. Prospective cohort study of respiratory effects at ages 14 to 26 following early life exposure to arsenic in drinking water. Environ Epidemiol 2020; 4:e089. [PMID: 32337474 PMCID: PMC7147401 DOI: 10.1097/ee9.0000000000000089] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 02/07/2020] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND We previously reported chronic respiratory effects in children who were then 7-17 years of age in Matlab, Bangladesh. One group of children had been exposed to high concentrations of arsenic in drinking water in utero and early childhood (average 436 µg/L), and the other group of children were never known to have been exposed to >10 µg/L. The exposed children, both males and females, had marked increases in chronic respiratory symptoms. METHODS The current study involves a further follow-up of these children now 14-26 years of age with 463 located and agreeing to participate. They were interviewed for respiratory symptoms and lung function was measured. Data were collected on smoking, body mass index (BMI), and number of rooms in the house as a measure of socioeconomic status. RESULTS Respiratory effects were still present in males but not females. In the high exposure group (>400 µg/L in early life) the odds ratio (OR) among male participants for dry cough in the last 12 months was 2.36 (95% confidence interval [CI] = 1.21, 4.63, P = 0.006) and for asthma OR = 2.51 (95% CI = 1.19, 5.29, P = 0.008). Forced vital capacity (FVC) was reduced in males in the early life high-exposure group compared with those never exposed (-95ml, P = 0.04), but not in female participants. CONCLUSIONS By the age range 14-26, there was little remaining evidence of chronic respiratory effects in females but pronounced effects persisted in males. Mechanisms for the marked male female differences warrant further investigation along with further follow-up to see if respiratory effects continue in males.
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Kim JB, Prunicki M, Haddad F, Dant C, Sampath V, Patel R, Smith E, Akdis C, Balmes J, Snyder MP, Wu JC, Nadeau KC. Cumulative Lifetime Burden of Cardiovascular Disease From Early Exposure to Air Pollution. J Am Heart Assoc 2020; 9:e014944. [PMID: 32174249 PMCID: PMC7335506 DOI: 10.1161/jaha.119.014944] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The disease burden associated with air pollution continues to grow. The World Health Organization (WHO) estimates ≈7 million people worldwide die yearly from exposure to polluted air, half of which-3.3 million-are attributable to cardiovascular disease (CVD), greater than from major modifiable CVD risks including smoking, hypertension, hyperlipidemia, and diabetes mellitus. This serious and growing health threat is attributed to increasing urbanization of the world's populations with consequent exposure to polluted air. Especially vulnerable are the elderly, patients with pre-existing CVD, and children. The cumulative lifetime burden in children is particularly of concern because their rapidly developing cardiopulmonary systems are more susceptible to damage and they spend more time outdoors and therefore inhale more pollutants. World Health Organization estimates that 93% of the world's children aged <15 years-1.8 billion children-breathe air that puts their health and development at risk. Here, we present growing scientific evidence, including from our own group, that chronic exposure to air pollution early in life is directly linked to development of major CVD risks, including obesity, hypertension, and metabolic disorders. In this review, we surveyed the literature for current knowledge of how pollution exposure early in life adversely impacts cardiovascular phenotypes, and lay the foundation for early intervention and other strategies that can help prevent this damage. We also discuss the need for better guidelines and additional research to validate exposure metrics and interventions that will ultimately help healthcare providers reduce the growing burden of CVD from pollution.
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Walker ES, Fedak KM, Good N, Balmes J, Brook RD, Clark ML, Cole-Hunter T, Dinenno F, Devlin RB, L'Orange C, Luckasen G, Mehaffy J, Shelton R, Wilson A, Volckens J, Peel JL. Acute differences in pulse wave velocity, augmentation index, and central pulse pressure following controlled exposures to cookstove air pollution in the Subclinical Tests of Volunteers Exposed to Smoke (SToVES) study. ENVIRONMENTAL RESEARCH 2020; 180:108831. [PMID: 31648072 PMCID: PMC6899199 DOI: 10.1016/j.envres.2019.108831] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 10/15/2019] [Accepted: 10/16/2019] [Indexed: 05/24/2023]
Abstract
Household air pollution emitted from solid-fuel cookstoves used for domestic cooking is a leading risk factor for morbidity and premature mortality globally. There have been attempts to design and distribute lower emission cookstoves, yet it is unclear if they meaningfully improve health. Using a crossover design, we assessed differences in central aortic hemodynamics and arterial stiffness following controlled exposures to air pollution emitted from five different cookstove technologies compared to a filtered air control. Forty-eight young, healthy participants were assigned to six 2-h controlled treatments of pollution from five different cookstoves and a filtered air control. Each treatment had a target concentration for fine particulate matter: filtered air control = 0 μg/m3, liquefied petroleum gas = 10 μg/m3, gasifier = 35 μg/m3, fan rocket = 100 μg/m3, rocket elbow = 250 μg/m3, three stone fire = 500 μg/m3. Pulse wave velocity (PWV), central augmentation index (AIx), and central pulse pressure (CPP) were measured before and at three time points after each treatment (0, 3, and 24 h). Linear mixed models were used to assess differences in the outcomes for each cookstove treatment compared to control. PWV and CPP were marginally higher 24 h after all cookstove treatments compared to control. For example, PWV was 0.15 m/s higher (95% confidence interval: -0.02, 0.31) and CPP was 0.6 mmHg higher (95% confidence interval: -0.8, 2.1) 24 h after the three stone fire treatment compared to control. The magnitude of the differences compared to control was similar across all cookstove treatments. PWV and CPP had no consistent trends at the other post-treatment time points (0 and 3 h). No consistent trends were observed for AIx at any post-treatment time point. Our findings suggest higher levels of PWV and CPP within 24 h after 2-h controlled treatments of pollution from five different cookstove technologies. The similar magnitude of the differences following each cookstove treatment compared to control may indicate that acute exposures from even the cleanest cookstove technologies can adversely impact these subclinical markers of cardiovascular health, although differences were small and may not be clinically meaningful.
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Hill LD, Pillarisetti A, Delapena S, Garland C, Pennise D, Pelletreau A, Koetting P, Motmans T, Vongnakhone K, Khammavong C, Boatman MR, Balmes J, Hubbard A, Smith KR. Machine-learned modeling of PM 2.5 exposures in rural Lao PDR. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 676:811-822. [PMID: 31071563 DOI: 10.1016/j.scitotenv.2019.04.258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 03/30/2019] [Accepted: 04/17/2019] [Indexed: 05/05/2023]
Abstract
This study presents a machine-learning-enhanced method of modeling PM2.5 personal exposures in a data-scarce, rural, solid fuel use context. Data collected during a cookstove (Africa Clean Energy (ACE)-1 solar-battery-powered stove) intervention program in rural Lao PDR are presented and leveraged to explore advanced techniques for predicting personal exposures to particulate matter with aerodynamic diameter smaller than 2.5 μm (PM2.5). Mean 48-h PM2.5 exposure concentrations for female cooks were measured for the pre- and post-intervention periods (the "Before" and "After" periods, respectively) as 123 μg/m3 and 81 μg/m3. Mean 48-h PM2.5 kitchen air pollution ("KAP") concentrations were measured at 462 μg/m3 Before and 124 μg/m3 After. Application of machine learning and ensemble modeling demonstrated cross-validated personal exposure predictions that were modest at the individual level but reasonably strong at the group level, with the best models producing an observed vs. predicted r2 between 0.26 and 0.31 (r2 = 0.49 when using a smaller, un-imputed dataset) and mean Before estimates of 119-120 μg/m3 and After estimates of 86-88 μg/m3. This offered improvement over one typical method of predicting exposure - using a kitchen exposure factor (the ratio of exposure to KAP)- which demonstrated an r2 ~ 0.03 and poorly estimated group average values. The results of these analyses highlight areas of methodological improvement for future exposure assessments of household air pollution and provide evidence for researchers to explore the advantages of further incorporating machine learning methods into similar research across wider geographic and cultural contexts.
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Fedak KM, Good N, Walker ES, Balmes J, Brook RD, Clark ML, Cole-Hunter T, Devlin R, L'Orange C, Luckasen G, Mehaffy J, Shelton R, Wilson A, Volckens J, Peel JL. Acute Effects on Blood Pressure Following Controlled Exposure to Cookstove Air Pollution in the STOVES Study. J Am Heart Assoc 2019; 8:e012246. [PMID: 31286826 PMCID: PMC6662148 DOI: 10.1161/jaha.119.012246] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Background Exposure to air pollution from solid fuel used in residential cookstoves is considered a leading environmental risk factor for disease globally, but evidence for this relationship is largely extrapolated from literature on smoking, secondhand smoke, and ambient fine particulate matter (PM2.5). Methods and Results We conducted a controlled human‐exposure study (STOVES [the Subclinical Tests on Volunteers Exposed to Smoke] Study) to investigate acute responses in blood pressure following exposure to air pollution emissions from cookstove technologies. Forty‐eight healthy adults received 2‐hour exposures to 5 cookstove treatments (three stone fire, rocket elbow, fan rocket elbow, gasifier, and liquefied petroleum gas), spanning PM2.5 concentrations from 10 to 500 μg/m3, and a filtered air control (0 μg/m3). Thirty minutes after exposure, systolic pressure was lower for the three stone fire treatment (500 μg/m3PM2.5) compared with the control (−2.3 mm Hg; 95% CI, −4.5 to −0.1) and suggestively lower for the gasifier (35 μg/m3PM2.5; −1.8 mm Hg; 95% CI, −4.0 to 0.4). No differences were observed at 3 hours after exposure; however, at 24 hours after exposure, mean systolic pressure was 2 to 3 mm Hg higher for all treatments compared with control except for the rocket elbow stove. No differences were observed in diastolic pressure for any time point or treatment. Conclusions Short‐term exposure to air pollution from cookstoves can elicit an increase in systolic pressure within 24 hours. This response occurred across a range of stove types and PM2.5 concentrations, raising concern that even low‐level exposures to cookstove air pollution may pose adverse cardiovascular effects.
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English P, Balmes J. Associations between Ozone and Fine Particulate Matter and Respiratory Illness Found to Vary between Children and Adults. Implications for U.S. Air Quality Policy. Am J Respir Crit Care Med 2019; 199:817-819. [PMID: 30485120 PMCID: PMC6444659 DOI: 10.1164/rccm.201811-2106ed] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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Payne-Sturges DC, Marty MA, Perera F, Miller MD, Swanson M, Ellickson K, Cory-Slechta DA, Ritz B, Balmes J, Anderko L, Talbott EO, Gould R, Hertz-Picciotto I. Healthy Air, Healthy Brains: Advancing Air Pollution Policy to Protect Children's Health. Am J Public Health 2019; 109:550-554. [PMID: 30789769 PMCID: PMC6417586 DOI: 10.2105/ajph.2018.304902] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/24/2018] [Indexed: 11/04/2022]
Abstract
Evidence is growing on the adverse neurodevelopmental effects of exposure to combustion-related air pollution. Project TENDR (Targeting Environmental Neurodevelopmental Risks), a unique collaboration of leading scientists, health professionals, and children's and environmental health advocates, has identified combustion-related air pollutants as critical targets for action to protect healthy brain development. We present policy recommendations for maintaining and strengthening federal environmental health protections, advancing state and local actions, and supporting scientific research to inform effective strategies for reducing children's exposures to combustion-related air pollution. Such actions not only would improve children's neurological development but also would have the important co-benefit of climate change mitigation and further improvements in other health conditions.
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Rhee J, Dominici F, Zanobetti A, Schwartz J, Wang Y, Di Q, Balmes J, Christiani DC. Impact of Long-Term Exposures to Ambient PM 2.5 and Ozone on ARDS Risk for Older Adults in the United States. Chest 2019; 156:71-79. [PMID: 30926395 DOI: 10.1016/j.chest.2019.03.017] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 02/27/2019] [Accepted: 03/01/2019] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Chronic exposures to particulate matter with an aerodynamic diameter < 2.5 μm (PM2.5) and ozone pollution can affect respiratory function. ARDS, an often lethal respiratory failure, is most common among older adults. However, few epidemiology studies have investigated an association between air pollution and the risk of ARDS. METHODS This observational study was conducted to estimate air pollution exposures at the ZIP code level and hospital admissions with ARDS among US Medicare beneficiaries aged ≥ 65 years from 2000 to 2012. A two-pollutant generalized linear mixed model, adjusting for sex, age, race, median household income, smoking, and weather, was applied. RESULTS There were a total of 1,164,784 hospital admissions with ARDS in the cohort. Increases of 1 µg/m3 in annual average PM2.5 and of 1 parts per billion in annual average ozone were associated with increases in annual hospital admission rates for ARDS of 0.72% (95% CI, 0.62-0.82) and 0.15% (95% CI, 0.08-0.22), respectively. In low-pollution regions (annual average PM2.5 level < 12 µg/m3 and annual average ozone level < 45 parts per billion), the same annual increase in PM2.5 and ozone were associated with increases in annual hospital admission rates for ARDS of 1.50% (95% CI, 1.27-1.72) and 0.27% (95% CI, 0.16-0.38). CONCLUSIONS Long-term exposures to PM2.5 and ozone were associated with increased risk of ARDS among older adults in the United States, including exposures below current annual US National Ambient Air Quality Standards.
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Tagle M, Pillarisetti A, Hernandez MT, Troncoso K, Soares A, Torres R, Galeano A, Oyola P, Balmes J, Smith KR. Monitoring and modeling of household air quality related to use of different Cookfuels in Paraguay. INDOOR AIR 2019; 29:252-262. [PMID: 30339298 PMCID: PMC6849814 DOI: 10.1111/ina.12513] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 10/12/2018] [Indexed: 06/02/2023]
Abstract
In Paraguay, 49% of the population depends on biomass (wood and charcoal) for cooking. Residential biomass burning is a major source of fine particulate matter (PM2.5 ) and carbon monoxide (CO) in and around the household environment. In July 2016, cross-sectional household air pollution sampling was conducted in 80 households in rural Paraguay. Time-integrated samples (24 hours) of PM2.5 and continuous CO concentrations were measured in kitchens that used wood, charcoal, liquefied petroleum gas (LPG), or electricity to cook. Qualitative and quantitative household-level variables were captured using questionnaires. The average PM2.5 concentration (μg/m3 ) was higher in kitchens that burned wood (741.7 ± 546.4) and charcoal (107.0 ± 68.6) than in kitchens where LPG (52.3 ± 18.9) or electricity (52.0 ± 14.8) was used. Likewise, the average CO concentration (ppm) was higher in kitchens that used wood (19.4 ± 12.6) and charcoal (7.6 ± 6.5) than in those that used LPG (0.5 ± 0.6) or electricity (0.4 ± 0.6). Multivariable linear regression was conducted to generate predictive models for indoor PM2.5 and CO concentrations (predicted R2 = 0.837 and 0.822, respectively). This study provides baseline indoor air quality data for Paraguay and presents a multivariate statistical approach that could be used in future research and intervention programs.
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Nightingale R, Lesosky M, Flitz G, Rylance SJ, Meghji J, Burney P, Balmes J, Mortimer K. Noncommunicable Respiratory Disease and Air Pollution Exposure in Malawi (CAPS). A Cross-Sectional Study. Am J Respir Crit Care Med 2019; 199:613-621. [PMID: 30141966 PMCID: PMC6396863 DOI: 10.1164/rccm.201805-0936oc] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 08/22/2018] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Noncommunicable respiratory diseases and exposure to air pollution are thought to be important contributors to morbidity and mortality in sub-Saharan African adults. OBJECTIVES We set out to explore the prevalence and determinants of noncommunicable respiratory disease among adults living in Chikhwawa District, Malawi. METHODS We performed a cross-sectional study among adults in communities participating in a randomized controlled trial of a cleaner-burning biomass-fueled cookstove intervention (CAPS [Cooking and Pneumonia Study]) in rural Malawi. We assessed chronic respiratory symptoms, spirometric abnormalities, and personal exposure to air pollution (particulate matter <2.5 μm in aerodynamic diameter [PM2.5] and carbon monoxide [CO]). Weighted prevalence estimates were calculated; multivariable and intention-to-treat analyses were done. MEASUREMENTS AND MAIN RESULTS One thousand four hundred eighty-one participants (mean [SD] age, 43.8 [17.8] yr; 57% female) were recruited. The prevalence of chronic respiratory symptoms, spirometric obstruction, and restriction were 13.6% (95% confidence interval [CI], 11.9-15.4), 8.7% (95% CI, 7.0-10.7), and 34.8% (95% CI, 31.7-38.0), respectively. Median 48-hour personal PM2.5 and CO exposures were 71.0 μg/m3 (interquartile range [IQR], 44.6-119.2) and 1.23 ppm (IQR, 0.79-1.93), respectively. Chronic respiratory symptoms were associated with current/ex-smoking (odds ratio [OR], 1.59; 95% CI, 1.05-2.39), previous tuberculosis (OR, 2.50; 95% CI, 1.04-15.58), and CO exposure (OR, 1.46; 95% CI, 1.04-2.05). Exposure to PM2.5 was not associated with any demographic, clinical, or spirometric characteristics. There was no effect of the CAPS intervention on any of the secondary trial outcomes. CONCLUSIONS The burden of chronic respiratory symptoms, abnormal spirometry, and air pollution exposures in adults in rural Malawi is of considerable potential public health importance. We found little evidence that air pollution exposures were associated with chronic respiratory symptoms or spirometric abnormalities and no evidence that the CAPS intervention had effects on the secondary trial outcomes. More effective prevention and control strategies for noncommunicable respiratory disease in sub-Saharan Africa are needed. Clinical trial registered with www.isrctn.com (ISRCTN 59448623).
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Padula AM, Yang W, Lurmann FW, Balmes J, Hammond SK, Shaw GM. Prenatal exposure to air pollution, maternal diabetes and preterm birth. ENVIRONMENTAL RESEARCH 2019; 170:160-167. [PMID: 30579990 PMCID: PMC6373725 DOI: 10.1016/j.envres.2018.12.031] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 12/03/2018] [Accepted: 12/14/2018] [Indexed: 05/21/2023]
Abstract
Prenatal exposure to ambient air pollution has been associated with preterm birth in several studies. Associations between air pollution and gestational or pre-existing diabetes have been hypothesized but are not well established. We examined the association between air pollution exposure in pregnancy and gestational diabetes and whether the association between air pollution and preterm birth is modified by diabetes (gestational or pre-existing) in a highly polluted area of California. Birth certificates and hospital discharge data from all singleton births from 2000 to 2006 to women living in four counties in the San Joaquin Valley of California were linked to criteria air pollution and traffic density measurements at the geocoded maternal residence. Air pollutants were dichotomized at the highest quartile and compared to the lower three quartiles. Logistic regression models were adjusted for maternal race-ethnicity, age, education, payment of birth expenses, and prenatal care. There were consistent inverse associations between exposure to air pollution during the first two trimesters and gestational diabetes (statistically significant odds ratios (OR) less than 1). When stratified by any diabetes (gestational or pre-existing), associations between air pollution exposure during pregnancy and categories of preterm birth (20-27, 28-31, 32-33, 34-36 weeks) were generally similar with few exceptions of exposures to carbon monoxide (CO) and particulate matter < 2.5 µm (PM2.5). Those with diabetes and exposure higher levels of CO (in first trimester or entire pregnancy) or PM2.5 (in first trimester) had higher risk of extremely preterm birth (20-27 weeks) compared with those without diabetes. The associations between traffic-related air pollution and gestational diabetes were in the unexpected ("protective") direction. Among those with any diabetes, associations were stronger between CO and PM2.5 and extremely preterm birth.
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Berger K, Eskenazi B, Balmes J, Kogut K, Holland N, Calafat AM, Harley KG. Prenatal high molecular weight phthalates and bisphenol A, and childhood respiratory and allergic outcomes. Pediatr Allergy Immunol 2019; 30:36-46. [PMID: 30338578 PMCID: PMC6436539 DOI: 10.1111/pai.12992] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 09/12/2018] [Accepted: 10/02/2018] [Indexed: 02/05/2023]
Abstract
BACKGROUND The prevalence of asthma and allergy is increasing in US children. In utero exposure to chemicals used in personal care products and plastics may contribute to increase in these diseases. METHODS We quantified urinary concentrations of eight phthalate metabolites and bisphenol A in mothers twice during pregnancy in 1999-2000 in Salinas, California. We assessed probable asthma, aeroallergies, eczema, and spirometry in their children at age 7, and measured T helper 1 and T helper 2 cells in blood at ages 2, 5, and 7 (N = 392). We employed Bayesian model averaging to select confounders from additional biomarkers measured in this population and controlled for them in logistic and linear regressions. RESULTS Monocarboxyisooctyl phthalate was associated with increased odds for probable asthma (odds ratio: 1.54, 95% CI: 1.12, 2.12), and with lower forced expiratory volume in one second (β: -0.09 L, 95% CI: -0.15, -0.03) and forced expiratory flow from 25% to 75% of forced vital capacity (β: -7.06 L/s, 95% CI: -11.04, -2.90). Several other associations were attenuated in final models that controlled for additional biomarkers. CONCLUSION Monocarboxyisooctyl phthalate was associated with lower respiratory health after controlling for related chemical exposure, which suggests that confounding by multiple chemical exposures should be considered in future research.
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Jamil S, Carlos WG, Leard L, Wang A, Santhosh L, Balmes J, Seam N, Dela Cruz CS. Wildfires Disaster Guidance: Tips for Staying Healthy during Wildfires. Am J Respir Crit Care Med 2019; 199:P3-P4. [PMID: 30644780 DOI: 10.1164/rccm.1992p3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Berger K, Eskenazi B, Balmes J, Holland N, Calafat AM, Harley KG. Associations between prenatal maternal urinary concentrations of personal care product chemical biomarkers and childhood respiratory and allergic outcomes in the CHAMACOS study. ENVIRONMENT INTERNATIONAL 2018; 121:538-549. [PMID: 30293015 PMCID: PMC6239199 DOI: 10.1016/j.envint.2018.09.027] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 09/13/2018] [Accepted: 09/16/2018] [Indexed: 05/19/2023]
Abstract
BACKGROUND Personal care product chemicals may be contributing to risk for asthma and other atopic illnesses. The existing literature is conflicting, and many studies do not control for multiple chemical exposures. METHODS We quantified concentrations of three phthalate metabolites, three parabens, and four other phenols in urine collected twice during pregnancy from 392 women. We measured T helper 1 (Th1) and T helper 2 (Th2) cells in their children's blood at ages two, five, and seven, and assessed probable asthma, aeroallergies, eczema, and lung function at age seven. We conducted linear and logistic regressions, controlling for additional biomarkers measured in this population as selected by Bayesian Model Averaging. RESULTS The majority of comparisons showed null associations. Mono-n-butyl phthalate (MnBP) was associated with higher Th2% (RR: 10.40, 95% CI: 3.37, 17.92), and methyl paraben was associated with lower Th1% (RR: -3.35, 95% CI: -6.58, -0.02) and Th2% at borderline significance (RR: -4.45, 95% CI: -8.77, 0.08). Monoethyl phthalate was associated with lower forced expiratory flow from 25 to 75% of forced vital capacity (FEF25-75%) (RR: -3.22 L/s, 95% CI: -6.02, -0.34). Propyl paraben (OR: 0.86, 95% CI: 0.74, 0.99) was associated with decreased odds of probable asthma. CONCLUSIONS While some biomarkers, particularly those from low molecular weight phthalates, were associated with an atopic cytokine profile and poorer lung function, no biomarkers were associated with a corresponding increase in atopic disease.
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Ortega Hinojosa AM, MacLeod KE, Balmes J, Jerrett M. Influence of school environments on childhood obesity in California. ENVIRONMENTAL RESEARCH 2018; 166:100-107. [PMID: 29883903 DOI: 10.1016/j.envres.2018.04.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 04/19/2018] [Accepted: 04/19/2018] [Indexed: 06/08/2023]
Abstract
OBJECTIVE To conduct a state-wide examination of public schools and the school neighborhood as potential targets for environmental public health tracking to address childhood obesity. METHODS We examined the relationship of social and physical environmental attributes of the school environment (within school and neighborhood) and childhood obesity in California with machine learning (Random Forest) and multilevel methods. We used data compiled from the California Department of Education, the U.S. Geological Survey, ESRI's Business Analyst, the U.S. Census, and other public sources for ecologic level variables for various years and assessed their relative importance to obesity as determined from the statewide Physical Fitness Test 2003 through 2007 for grades 5, 7, and 9 (n = 5,265,265). RESULTS In addition to individual-level race and gender, the following within and school neighborhood variables ranked as the most important model contributors based on the Random Forest analysis and were included in multilevel regressions clustered on the county. Violent crime, English learners, socioeconomic disadvantage, fewer physical education (PE) and fully credentialed teachers, and diversity index were positively associated with obesity while academic performance index, PE participation, mean educational attainment and per capita income were negatively associated with obesity. The most highly ranked built or physical environment variables were distance to the nearest highway and greenness, which were 10th and 11th most important, respectively. CONCLUSIONS Many states in the U.S. do not have school-based surveillance programs that collect body mass index data. System-level determinants of obesity can be important for tracking and intervention. The results of these analyses suggest that the school social environment factors may be especially important. Disadvantaged and low academic performing schools have a higher risk for obesity. Supporting such schools in a targeted way may be an efficient way to intervene and could impact both health and academic outcomes. Some of the more important variables, such as having credentialed teachers and participating in PE, are modifiable risk factors.
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Havens D, Wang D, Grigg J, Gordon SB, Balmes J, Mortimer K. The Cooking and Pneumonia Study (CAPS) in Malawi: A Cross-Sectional Assessment of Carbon Monoxide Exposure and Carboxyhemoglobin Levels in Children under 5 Years Old. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:ijerph15091936. [PMID: 30189674 PMCID: PMC6163876 DOI: 10.3390/ijerph15091936] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 08/22/2018] [Accepted: 08/30/2018] [Indexed: 12/31/2022]
Abstract
Household air pollution is estimated to cause half a million deaths from pneumonia in children worldwide. The Cooking and Pneumonia Study (CAPS) was conducted to determine whether the use of cleaner-burning biomass-fueled cookstoves would reduce household air pollution and thereby the incidence of pneumonia in young children in rural Malawi. Here we report a cross-sectional assessment of carbon monoxide (CO) exposure and carboxyhemoglobin (COHgB) levels at recruitment to CAPS. Mean (SD; range) 48-h CO exposure of 1928 participating children was 0.90 (2.3; 0–49) ppm and mean (SD; range) COHgB level was 5.8% (3.3; 0–20.3). Higher mean CO and COHgB levels were associated with location (Chikhwawa versus Chilumba) (OR 3.55 (1.73–7.26)); (OR 2.77 (1.08–7.08)). Correlation between mean CO and COHgB was poor (Spearman’s ρ = 0.09, p < 0.001). The finding of high COHgB levels in young children in rural Malawi that are at levels at which adverse neurodevelopmental and cognitive effects occur is of concern. Effective approaches for reducing exposure to CO and other constituents of air pollution in rural sub-Saharan African settings are urgently needed.
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Lawin H, Fanou LA, Kpangon AA, Hinson AV, Balmes J, Wanjiku J, Ale BM, Fayomi B. Comparison of motorcycle taxi driver's respiratory health using an air quality standard for carbon monoxide in ambient air: a pilot survey in Benin. Pan Afr Med J 2018; 30:113. [PMID: 30364347 PMCID: PMC6195239 DOI: 10.11604/pamj.2018.30.113.14975] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 05/25/2018] [Indexed: 11/11/2022] Open
Abstract
Introduction Ambient air quality standards are not designed to protect people occupationally exposed to outdoor air pollution on a routine basis. This study aimed to assess the effect of exceeding the US ambient air quality standard for carbon monoxide (CO) on motorcycle taxi drivers respiratory health. Methods A cross-sectional study of 85 current motorcycle taxi drivers with at least 5 years of job tenure in Cotonou (Benin) was conducted. Personal CO was measured with a portable CO data logger for 8 hours per day during working hours. A questionnaire on respiratory symptoms was administered to participants and spirometry was performed. Participants were divided into two groups, those with exposure to CO >9 ppm and ≤9 ppm, according to the US Environmental Protection Agency (EPA) National Ambient Air Quality Standard which is an 8-hour average of 9ppm. 8 and 10 ppm were also used an exposure limit. Analysis was done using these two groups. Results Socio-demographic characteristics were well balanced between the two study groups. The drivers with a CO exposure of more than 9ppm had non-significantly more respiratory symptoms (OR=1.67; 95%CI:0.26,10.74), lower FVC and FEV1 compared to the less exposed group but they have a significant lower PEF (-10%, p=0.02). When we used an exposure limit of 8 or 10 ppm the results were not statistically different. Conclusion Drivers with a CO exposure >9 ppm tend to have more respiratory problems. More research is needed to reinforce this result in order to improve air quality standards to protect workers occupationally exposed to outdoor air pollution.
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Holm SM, Balmes J, Gillette D, Hartin K, Seto E, Lindeman D, Polanco D, Fong E. Cooking behaviors are related to household particulate matter exposure in children with asthma in the urban East Bay Area of Northern California. PLoS One 2018; 13:e0197199. [PMID: 29874253 PMCID: PMC5991365 DOI: 10.1371/journal.pone.0197199] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2017] [Accepted: 04/27/2018] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND Asthma is a common childhood disease that leads to many missed days of school and parents' work. There are multiple environmental contributors to asthma symptoms and understanding the potential factors inside children's homes is crucial. METHODS This is a dual cohort study measuring household particulate matter (PM2.5), behaviors, and factors that influence air quality and asthma symptoms in the urban homes of children (ages 6-10) with asthma; one cohort had cigarette smoke exposure in the home (n = 13) and the other did not (n = 22). Exposure data included measurements every 5 minutes for a month. RESULTS In the entire study population, a large contributor to elevations in indoor PM2.5 above 35 μg/m3 was not using the stove hood when cooking (8.5% higher, CI 3.1-13.9%, p<0.005). Median PM values during cooking times were 0.88 μg/m3 higher than those during non-cooking times (95% CI 0.33-1.42). Mean monthly household PM2.5 level was significantly related to the presence of a cigarette smoker in the home (10.1 μg/m3 higher, 95% CI 5.2-15.1, p<0.001) when controlling for use of the stove hood and proximity to major roadway. There was a trend toward increased odds of persistent asthma with increases in average monthly PM2.5 (OR 1.1, 95% CI 0.97-1.3, p = 0.16). CONCLUSIONS Consideration of only outdoor PM2.5 may obscure potentially modifiable risks for asthma symptoms. Specifically, this preliminary study suggests that cooking behaviors may contribute to the burden of PM2.5 in the homes of children with asthma and thus to asthma symptoms.
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Nardone A, Neophytou AM, Balmes J, Thakur N. Ambient Air Pollution and Asthma-Related Outcomes in Children of Color of the USA: a Scoping Review of Literature Published Between 2013 and 2017. Curr Allergy Asthma Rep 2018; 18:29. [PMID: 29663154 PMCID: PMC6198325 DOI: 10.1007/s11882-018-0782-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE OF REVIEW Given racial disparities in ambient air pollution (AAP) exposure and asthma risk, this review offers an overview of the literature investigating the ambient air pollution-asthma relationship in children of color between 2013 and 2017. RECENT FINDINGS AAP is likely a key contributor to the excess burden of asthma in children of color due to pervasive exposure before birth, at home, and in school. Recent findings suggest that psychosocial stressors may modify the relationship between AAP and asthma. The effect of AAP on asthma in children of color is likely modulated by multiple unique psychosocial stressors and gene-environment interactions. Although children of color are being included in asthma studies, more research is still needed on impacts of specific criteria pollutants throughout the life course. Additionally, future studies should consider historical factors when analyzing current exposure profiles.
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Sood A, Assad NA, Barnes PJ, Churg A, Gordon SB, Harrod KS, Irshad H, Kurmi OP, Martin WJ, Meek P, Mortimer K, Noonan CW, Perez-Padilla R, Smith KR, Tesfaigzi Y, Ward T, Balmes J. ERS/ATS workshop report on respiratory health effects of household air pollution. Eur Respir J 2018; 51:51/1/1700698. [PMID: 29301918 DOI: 10.1183/13993003.00698-2017] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 08/08/2017] [Indexed: 12/18/2022]
Abstract
Exposure to household air pollution (HAP) from solid fuel combustion affects almost half of the world population. Adverse respiratory outcomes such as respiratory infections, impaired lung growth and chronic obstructive pulmonary disease have been linked to HAP exposure. Solid fuel smoke is a heterogeneous mixture of various gases and particulates. Cell culture and animal studies with controlled exposure conditions and genetic homogeneity provide important insights into HAP mechanisms. Impaired bacterial phagocytosis in exposed human alveolar macrophages possibly mediates several HAP-related health effects. Lung pathological findings in HAP-exposed individuals demonstrate greater small airways fibrosis and less emphysema compared with cigarette smokers. Field studies using questionnaires, air pollution monitoring and/or biomarkers are needed to better establish human risks. Some, but not all, studies suggest that improving cookstove efficiency or venting emissions may be associated with reduced respiratory symptoms, lung function decline in women and severe pneumonia in children. Current studies focus on fuel switching, stove technology replacements or upgrades and air filter devices. Several governments have initiated major programmes to accelerate the upgrade from solid fuels to clean fuels, particularly liquid petroleum gas, which provides research opportunities for the respiratory health community.
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